ViZn Energy: A New Flow Battery Contender in the Grid-Scale Storage RaceFor years, battery technology startups and researchers have been striving to create a rechargeable, grid-scale energy storage system using zinc, one of the world’s cheapest and most plentiful metals. Zinc-based batteries tend to break down after just hundreds of charge-discharge cycles, however -- and coming up with new technology innovations to overcome this remains a challenge.
Take the example of ViZn Energy Systems, a startup with a zinc-iron flow battery it’s now putting to the test in grid-scale applications. For the past four years, ViZn (pronounced “vision”) has been busy turning a fundamental weakness of its alkaline-based electrolyte chemistry into a key advantage.
Founded in 2009 as Zinc Air Inc., the Columbia Falls, Mont.-based startup changed its name in September and launched its first commercial-scale product, an 80-kilowatt, 160-kilowatt-hour zinc redox flow battery housed in a 20-foot shipping container. It also announced its first deployment with BlueSky Energy for an Austrian microgrid project, aimed at storing and balancing on-site solar generation.
In March, ViZn announced that Kalispell, Mont.-based utility Flathead Electric Cooperative had installed a second system, meant to test a variety of grid support services. And this week, grid energy storage software and systems startup Greensmith named ViZn as one of the battery providers it’s working with at grid scale.
ViZn’s Z20 systems are targeting a price point of $800 per kilowatt-hour for microgrid systems, Kirk Plautz, vice president of sales, told me in a July interview. The company’s longer-term goal is to put together five of these containers in a 1-megawatt, 3 megawatt-hour system, the GS200, with a “clear path” to reducing those costs to about $450 per kilowatt-hour at scale, he said.
That’s on par with the costs being targeted by other flow battery competitors, whether they’re using vanadium (UniEnergy, Imergy and Cellcube), iron-chromium (EnerVault) or zinc-bromine chemistries (Primus Power, ZBB, RedFlow). Flow batteries pump electrolyte through electrochemical cells, and thus can add more tanks of electrolyte to expand their energy capacity, something sealed batteries can’t do. They aren’t as efficient as the latest lithium-ion batteries, however, and can’t compete on how much power they're able to deliver at any one time.
One of ViZn’s key differentiators is its use of an alkaline, rather than acidic, electrolyte to get the job done, executive vice president Craig Wilkins told me. That alkaline chemistry, developed over the course of nearly a decade of research at Lockheed Martin, was aimed at avoiding the dendrite formation and subsequent failure common to acidic-based zinc battery chemistries, he said.
theenergycollective
Human history becomes more and more a race between education and catastrophe. H. G. Wells.
Fatih Birol's motto: leave oil before it leaves us.